Volvo HU850 stereo system

[Skippy4738]

Hi,
I've just joined the website. I own a 2005 XC70 and although I've had Volvo's since 1985, I've not, till now had one this difficult to resolve. The lights, barring the LCD display have all gone out on the head unit. I spoke to the main dealer, who wanted to charge me £132 just to look at it, the specialist I take it to for servicing is somewhat bemused, Volvo customer services say to buy a new unit at over £600, and a radio repairer told me he'd seen this problem before and it is the car not telling the lights to come on, rather than a fault with the radio!! This means that even if I were to replace the radio, the lights still might not work. Now I'm confused. Has anyone had this problem before, and if so how can you cure it? Can anyone help me please.
Dave

[JDS60R]

The radio takes an electric input on when to power the lights. Use the wiring diagrams in the repair section. Or just test the plugs for which wire is the signal form the light switch.

Many of the aftermarket radio companies have free access to their installation manual. That should also contain which wire is which for illumination signal. If the signals are right then you could assume its the radio.

I'm assuming that someone has checked already for burnt out bulbs and loose connections. If not - do that first.

[weapon2006]

Hello, my 06 XC70 (4C susp, HU-850, 99440 mi) has the same problem, it started about 6 months ago. The main display works however the back lights do not. Last week it worked briefly when I turned the key from position I to III and started the engine. After the engine had ran for 5 seconds the back lights shut off and have not come on again since. Did you find the solution by using the wiring diagrams in the repair section? If so, what was the location of the culprit?

[Chopper]

Hi Guys, I was just wondering if anyone had found a solution for this problem with the lights not being activated when the ignition is turned on. I love my XC70 and although the lights on the radio are not really a major issue they just bug me for not working